West syndrome
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(Hypsarrhythmia, flexor spasms)
Estimated incidence of 1/3,000 births. Association of infantile spasms, a typical intercritical EEG (hypsarythmia) and mental retardation. The syndrome is caused in about 80 % of cases by a brain abnormality: neonatal hypoxia, sequelae of infection, isolated malformation or associated with other abnormalities (Bourneville tuberous sclerosis, or phenylcetonuria for example). In about 10 % of cases, no cause or lesion is found: this is called cryptogenic West syndrome. The prognosis is better for cryptogenic forms of West syndrome.
West syndrome is a form of epilepsy (15-50 % of infant epilepsy) that usually occurs in the small infant (starting classically around 5 months of age, but cases have been described that started up to 5 years) by:
The spasms tend to decrease or disappear before 5 years of age but relapses are observed.
Treatment: vigabatrine is the first choice; in case of failure, hydrocortisone or ACTH treatments are associated. Other antiepileptics or a ketogenic diet are associated in case of treatment-resistant epilepsy. Epilepsy surgery is used only for localized brain malformations.
Anesthetic implications:
treatment-resistant epilepsy, mental retardation.
In case of a ketogenic diet:
- take advice from the neuropediatrician: efficacy of the diet, which treatment in case of seizure, side effects (urinary lithiases ?) - evaluation: RBC, WC, platelets, electrolytes, urea, creatinine, Ca, Mg, albumin and prealbumin (nutrition). SGOT and SGPT levels are often moderately elevated - avoid prolonged fasting: clear unsweetened fluids allowed - avoid sweetened fluids in the premedication - avoid IV administration of carbohydrates containing IV fluids - check glycemia at induction: ideally 50-80 mg/dL |
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anesthesia |
- propofol: OK for induction but avoid TIVA: source of glycerol, risk of PRIS and pancreatitis - fluids: 0.9 % NaCl (risk of worsening metabolic acidosis) or Ringer lactate (but lactate promotes gluconeogenesis) - avoid corticosteroids: dexamethasone? - avoid carbohydrate-containing medications (glucose, mannitol, glycerol) if possible - the transfusion of labile blood products is a hidden intake of carbohydrates - in case of hypoglycemia, correct with low doses of glucose (0.25g/kg) - monitor glycemia, pH, electrolytes, NaHCO3 |
postoperative |
- resume the ketogenic diet as soon as possible - check ketone bodies (urine): between 40 and 160 mg/dL or at least 2 ++ |
Ketogenic diet: perianesthetic recommendations
References :
- Niesen AD, Jacob AK, Aho LE, Botten EJ, Nase KE, Nelson JM, Kopp SL.
Perioperative seizures in patients with a history of seizure disorder.
Anesth Analg 2010; 111:729-35.
- McNeely JK.
Perioperative management of a paediatric patient on the ketogenic diet.
Pediatr Anesth 2000; 10:103-6.
- Baumeister FA, Oberhoffer R, Liebhaber GM.
Fatal propofol infusion syndrome in association with ketogenic diet.
Neuropaediatrics 2004; 35:250-2.
- Conover ZR, Talai A, Klockau KS, Ing RJ, Chaterjee D.
Perioperative management of children on ketogenic dietary therapies.
Anesth Analg 2020 ; 131 :1872-82.
Updated: November 2020